Looking for some wise ADVICE. Have some questions that I've been pondering for my new project. 2 questions for 1 Thread

1). I have a 400 GM sbc. My plan is to stroke it to 421 ci. However, I'm unsure of the clearance between the oil pan and the cross-member of the frame, being that the oil pan will be different based on the changed demensions of the bottom end of the engine. Will this drop into the engine bay without modifications, or what/how changes are needed to fit engine. Also what part number for oil pan?

2). The 421 build will consists of a stout forged bottom end(of Course). AFR heads ( 195 for torque or 210,220 for balanced tq/hp), 10.5-11.0 compression, 750 or bigger carb, and Leaning for a 3000 stall for street/strip Use. I would love to have some advice on cam selection( hyr roller & hyr solid) but NOTHING from Comp Cams!!! I was considering a range of 236-260 @.050. For 195 heads shooting for 600tq and 550-ish hp. For other Heads 600/600 hp/tq respectively.

Please help me with My Weekend Warrior!!! looking to run 10's and possibly a 125 shot of H-2-O..LOL for low 9's...... OR SHOULD I JUST CONSIDER A 406 ci. Please PM me if you'll like. Thanks

Looking for some wise ADVICE. Have some questions that I've been pondering for my new project. 2 questions for 1 Thread

1). I have a 400 GM sbc. My plan is to stroke it to 421 ci. However, I'm unsure of the clearance between the oil pan and the cross-member of the frame, being that the oil pan will be different based on the changed demensions of the bottom end of the engine. Will this drop into the engine bay without modifications, or what/how changes are needed to fit engine. Also what part number for oil pan?

2). The 421 build will consists of a stout forged bottom end(of Course). AFR heads ( 195 for torque or 210,220 for balanced tq/hp), 10.5-11.0 compression, 750 or bigger carb, and Leaning for a 3000 stall for street/strip Use. I would love to have some advice on cam selection( hyr roller & hyr solid) but NOTHING from Comp Cams!!! I was considering a range of 236-260 @.050. For 195 heads shooting for 600tq and 550-ish hp. For other Heads 600/600 hp/tq respectively.

Please help me with My Weekend Warrior!!! looking to run 10's and possibly a 125 shot of H-2-O..LOL for low 9's...... OR SHOULD I JUST CONSIDER A 406 ci. Please PM me if you'll like. Thanks

the 421/427 is a great motor. In respect to AFR both heads are great but the size of this motor could utilize the 210s. If you want the best cam possible for the ride call most any manufacturer or all of them for a custom grind. They are gonna ask you questions about your ride, such as weight, gears, use of the ride, and details of the motor. As far as solid or hyd. roller, the hyd. will be better for durability in all valvetrain operation. The solid is violent on the valves and seats because of the extra spring pressure. Either have the power potential you are looking for. Also you may need more carb and good exaust. Alot of people overlook the headers/ exaust system. There is alot of intake/ carb choices just look at what your pocket can handle.

Looking for some wise ADVICE. Have some questions that I've been pondering for my new project. 2 questions for 1 Thread

1). I have a 400 GM sbc. My plan is to stroke it to 421 ci. However, I'm unsure of the clearance between the oil pan and the cross-member of the frame, being that the oil pan will be different based on the changed demensions of the bottom end of the engine. Will this drop into the engine bay without modifications, or what/how changes are needed to fit engine. Also what part number for oil pan?

2). The 421 build will consists of a stout forged bottom end(of Course). AFR heads ( 195 for torque or 210,220 for balanced tq/hp), 10.5-11.0 compression, 750 or bigger carb, and Leaning for a 3000 stall for street/strip Use. I would love to have some advice on cam selection( hyr roller & hyr solid) but NOTHING from Comp Cams!!! I was considering a range of 236-260 @.050. For 195 heads shooting for 600tq and 550-ish hp. For other Heads 600/600 hp/tq respectively.

Please help me with My Weekend Warrior!!! looking to run 10's and possibly a 125 shot of H-2-O..LOL for low 9's...... OR SHOULD I JUST CONSIDER A 406 ci. Please PM me if you'll like. Thanks

Use whatever oil pan you want to. If there is anything in the way, such as a crossmember, chop it out of there and rebuild a custom crossmember further forward or rearward out of 3" x 3" x 0.120" wall tubing.

10.5-11.0 will require more cam than you can support with a 3000 stall converter. Use more converter or less SCR and therefore, less cam and therefore, less power.

With all due respect, you have no idea what it takes to run in the nines.

I wouldn't do a 421 in a stock block if that is what you have. A lot of clearancing to be done with 3.875" stroke, might hit water, will need small base circle cam and likely 2.00" rod journals and small journal stroker clearanced rods, with the increased likelyhood of the stock block failing and taking your more expensive rotating assembly with it. 406 will get you to that power level and not be as expensive in parts and time. If you have a Dart block then the 421 or bigger makes more sense.

Can't tell you what is up on the oil pan until you tell us what chassis it is going in. Most are no problem but a few are.

195 head is way too small, you need to treat this like it was a small big block, 220 or bigger heads, 900 or bigger carb, no hydraulic anything, it will need solid flat tappet or solid roller to meet a 600hp goal. 256°@.050" intake side or bigger, .630"+ lift, 104-108° seperation. The smart man gets a custom grind as has been noted.

3000 rpm stall is 1000 minimum too low, and yes 4000+ is street friendly, it only stalls that high at full throttle from a stop, will behave nearly like normal in cruising because torque converters are a load sensitive device. They are not like a slipper clutch on a minibike. 4.30 or more gear depending on tire size.

This will get you to 10.60-10.70 ET at 3000 lbs, if you want more it will need more of everything - cam, compression, stall, gear. The 125 shot will only drop that to about 10.25 from the 10.60 baseline. You want low nines you are going to have to spray it with 350+hp N20 or get 500lbs out of the car.

the car will be a full size 86 Monte Carlo w/ 4:10 gears out back. I see AFR 210 as heads and possibly increasing the cmpression based on my desired track times. Thanks for the input. If there are combo out for the 421 or 406 please forward the link.

the car will be a full size 86 Monte Carlo w/ 4:10 gears out back. I see AFR 210 as heads and possibly increasing the cmpression based on my desired track times. Thanks for the input. If there are combo out for the 421 or 406 please forward the link.

No problems with a pan in that chassis, there are several options from several manufacturers that will fit the bill. Won't need any crossmember mods unless you want to get really wild with SuperStock or similar full length kick-out max effort race pans with all the baffles, scrapers, trap doors, etc.

Hope you have something a lot better than the stock size 7.5" rear axle in that Monte, it is only good for about 350 hp with sticky tires before it blows up. Very weak rear end, no way to beef it up adequately. You need a Grand National/Hurst Olds/Olds 442 10-bolt 8.5" rear, or an aftermarket 12-bolt, Dana 60, or 9" Ford

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